Tums, have you checked to see the natural current in your pond due to wind and natural heating? I found that my pond has a current at all times.
My main pond has constant current too.
It has a lot to do with the 500,000 volt powerline that goes directly over it.
Actually, we do have a lot of natural water currents too. Like High Flyer's, we have constant wind. Except when iced over, we never even have a thermocline. The water is always moving.
